Conventional mechanically and electronically integrated motor control apparatuses, in which a motor element and a control substrate are provided integrally with each other, include a magnet fixed to an end of a motor shaft that is located closer to the control substrate, and detect a rotational angle of a motor rotor by detecting a change in a strength and a direction of a magnetic field of the magnet with use of a magnetic sensor mounted on the control substrate.
In the above-described motor control apparatuses, power is supplied from a power substrate to a stator via a bus bar. When the motor is driven, a high current flows through the bus bar, so that a strong magnetic field is generated around the bus bar. This magnetic field generated from the bus bar exerts an influence on the magnetic sensor, leading to deterioration of detection accuracy.
PTL 1 discusses a technique that covers the magnet with a cover member attached to a housing. The cover member is made from a magnetic material, and therefore absorbs the magnetic field generated from the bus bar. This configuration can eliminate or reduce the influence of the magnetic field from the bus bar on the magnetic field generated from the magnet.